No abstract

The effects of in situ plasma pretreatment of air-exposed TiN-covered silicon substrates and deposition temperature on surface topography and the gap-filling properties were investigated. Plasma pretreatment before Al deposition inevitably resulted in a lowering of the surface roughness of the Al films, regardless of the pretreatment conditions investigated. However, despite its effect upon the surface morphology, such a treatment was not effective in terms of improving the hole filling capability, probably due to the insufficiently treated TiN on the sidewalls of via holes and the low diffusion rate of the reactants into the holes. Deposition temperature was also found to affect the surface morphology of Al films. Higher deposition temperature strongly favored smoother films and the roughness, quantified by reflectance, was reduced by a factor of three when the deposition temperature was increased by 100ЊC.